| abstract |
The present invention relates to a compound of the general formula (I): <CHEM> ÄAr1 is aryl fused to the adjacent pyrazinone ring at the 5th and 6th positions, etc., X is CO, etc., Y is CH, etc., Z is CH, etc., V is CH, etc., Wn is -(CH2)n- (n is zero to four), R1 is H or optionally substituted lower alkyl, etc., R2 is H, etc., R3 and R4 are the same or different and are each H, etc., R5 and R6 are the same or different and are each H, hydroxy, etc.Ü or a pharmaceutically acceptable salt or ester thereof; a pharmaceutical composition, an inhibitor of Cdk4 and/or Cdk6 or an anti-cancer agent, containing the same as an active ingredient; and a process for preparing them. |